echarts折线图自定义打点标记小工具
由于没研究明白echarts怎么用label和lableLine实现自定义打点标记，索性用markPoint把长方形压扁成线模拟了一番自定义打点标记，记录下来备用。（markLine同理也能实现）
实现代码如下：
<!DOCTYPE html>
<html lang="en" style="height:100%;"><head><meta charset="utf-8"></head><body style="height:100%;margin:0;"><div><form>显示文本 <input id="name" />旋转角度 <input id="rotate" />指示线长 <input id="size" />横坐标 <input id="x" /><input type="button" onclick="add()" value="添加" /><input type="button" onclick="del()" value="删除" /><input type="button" onclick="edit()" value="修改" /></form></div><div id="container" style="height:100%;" /><script type="text/javascript" src="https://registry.npmmirror.com/echarts/5.5.0/files/dist/echarts.min.js"></script><script type="text/javascript">var data = [['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun'],[10, 11, 13, 11, 12, 12, 9]];var index = -1;var dom;var myChart;var items = [{name: '显示1',symbolRotate: 45,symbolSize: 60,coord: ['Mon', 10],}, {name: '显示2',symbolRotate: 225,symbolSize: 60,coord: ['Fri', 12]}];function init() {if(!dom) {dom = document.getElementById('container');}if(!myChart) {myChart = echarts.init(dom, null, {renderer: 'canvas',useDirtyRect: false});}var markPoint = [];for(var item of items) {var symbolOffset = [-item.symbolSize / 2 * Math.sin(item.symbolRotate / 180 * Math.PI),-item.symbolSize / 2 * Math.cos(item.symbolRotate / 180 * Math.PI)];var position;if((item.symbolRotate >= 0 && item.symbolRotate <= 90) || (item.symbolRotate >= 270 && item.symbolRotate <= 360)) {position = 'top';} else {position = 'bottom';}markPoint.push({coord: item.coord,value: item.name,symbolSize: [1, item.symbolSize],symbolRotate: item.symbolRotate,symbolOffset: symbolOffset,label: {show: true,position: position,color: '#000000',offset: [symbolOffset[0], 0]}});}var option = {tooltip: {axisPointer: {type: 'cross'}},xAxis: {axisTick: {alignWithLabel: true},data: data[0]},yAxis: {scale: true},series: [{name: '温度',type: 'line',data: data[1],smooth: true,markPoint: {symbol: 'rect',itemStyle: {color: '#000000',},data: markPoint}}]};myChart.setOption(option);}function clear() {index = -1;document.getElementById('name').value = '';document.getElementById('rotate').value = '';document.getElementById('size').value = '';document.getElementById('x').value = '';}function add() {if(index !== -1) {return;}var name = document.getElementById('name').value;if(!name) {return;}var rotate = document.getElementById('rotate').value;if(!rotate) {document.getElementById('rotate').value = rotate = 0;}var size = document.getElementById('size').value;if(!size) {document.getElementById('size').value = size = 60;}var x = document.getElementById('x').value;if(!x) {return;}var item = {name: name,symbolRotate: rotate,symbolSize: size,coord: [x, 0]}for(var i in data[0]) {if(item.coord[0] === data[0][i]) {item.coord[1] = data[1][i];break;}}items.push(item);index = items.length - 1;init();}function del() {if(index === -1) {return;}items.splice(index, 1);clear();init();}function edit() {if(index === -1) {return;}items[index].name = document.getElementById('name').value;items[index].symbolRotate = document.getElementById('rotate').value;items[index].symbolSize = document.getElementById('size').value;items[index].coord[0] = document.getElementById('x').value;for(var i in data[0]) {if(items[index].coord[0] === data[0][i]) {items[index].coord[1] = data[1][i];break;}}init();}init();window.addEventListener('resize', myChart.resize);myChart.on('click', (params) => {clear();if(params.componentType === 'markPoint') {for(var i in items) {if(params.data.value === items[i].name) {index = i;document.getElementById('name').value = items[i].name;document.getElementById('rotate').value = items[i].symbolRotate;document.getElementById('size').value = items[i].symbolSize;document.getElementById('x').value = items[i].coord[0];break;}}} else if(params.componentType === 'series') {for(var i in items) {if(params.name === items[i].coord[0]) {index = i;document.getElementById('name').value = items[i].name;document.getElementById('rotate').value = items[i].symbolRotate;document.getElementById('size').value = items[i].symbolSize;break;}}document.getElementById('x').value = params.name;}});</script></body>
</html>
实现效果如下：
